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Position-Time Graphs - Conceptual Analysis - help9

The slope of a position-time graph is equal to the velocity of the object. The steeper that a line is (whether sloping up or sloping down), the greater the velocity of the object.

There are three very similar versions of this question. Each version provides three lines on a position-time graph, each with a different slope. The question asks the learner to rank the three objects in order of increasing speed. One of the versions is shown below.

Version 1
The motions of Objects A, B, and C are represented on a position-time graph. Observe their lines and rank the speeds of Objects A, B, and C from slowest to fastest.

In this question you have to inspect the three lines on the graph and rank the speeds of the object from smallest to middlest to greatest. The slope of the line on a position-time graph is the velocity. So this question involves comparing the slopes of the three lines. Two of the lines slope upward and one line slopes downward. But that really doesn't matter. You need to focus on how steeply or how gently the lines are sloped. A gently-sloped line is nearly horizontal; it has the smallest slope and represents the object that is moving slowest. A steeply-sloped line is just the opposite; it would have a large upward or downward slant to it. You might say it is the line with the greatest rise (or fall) for any given run. The most steeply-sloped line is the line with the greatest slope and represents the object that is moving fastest (has the greatest speed).

Try the links below to our Tutorial for more information about position-time graphs:

The Meaning of Shape for a p-t Graph

The Meaning of Slope for a p-t Graph

Determining the Slope on a p-t Graph